Problem with commiting a String to a Stateful Widget - flutter

Question

I want to create a ModalBottomSheet, which opens a lot of RaisedButtons. These buttons should change there Color after pressing.
Therefore I created a StatefulWidget named "Buttons".
In my MainClass i use
for (String item in myList) Buttons(item)
to commit the Strings of myList to Buttons.
But i have 2 Problems in Buttons:
String item should be final, but then i can't use it as a setter
(I want to get rid of the blue underlining of Buttons, which tell me: This class (or a class that this class inherits from) is marked as '#immutable', but one or more of its instance fields aren't final: )
The other problem is, that in my buildMethod "item" isn't defined.
Why can't I use String item in my build Method?
class Buttons extends StatefulWidget {
String item;
Buttons(String item) {
this.item = item;
}
#override
_ButtonsState createState() => _ButtonsState();
}
class _ButtonsState extends State<Buttons> {
bool pressAttention = false;
#override
Widget build(BuildContext context) {
return Container(
child: Card(
child: RaisedButton(
child: Text(item),
color: pressAttention ? Colors.grey : Colors.blue,
onPressed: () => setState(() => pressAttention = !pressAttention),
),
),
);
}
}

Answer 1

Replace Text(item) by Text(widget.item)
class Buttons extends StatefulWidget {
final String item;
Buttons(this.item);
#override
_ButtonsState createState() => _ButtonsState();
}
class _ButtonsState extends State<Buttons> {
bool pressAttention = false;
#override
Widget build(BuildContext context) {
return Container(
child: Card(
child: RaisedButton(
child: Text(widget.item),
color: pressAttention ? Colors.grey : Colors.blue,
onPressed: () => setState(() => pressAttention = !pressAttention),
),
),
);
}
}